SEATTLE (AP)  A judge in Washington has thrown out more than 300,000 signatures to put a gun-control initiative on the November ballot, saying the petition format did not follow election law.

Thurston County Superior Court Judge James Dixon said Friday the signature petitions for Initiative 1639 did not clearly identify what would change in the law and the font was too small to be readable. He ordered the secretary of state”s office to stop certification of the ballot measure.

The National Rifle Association and Bellevue-based Second Amendment Foundation had filed a lawsuit against Secretary of State Kim Wyman to get the initiative off the ballot, arguing the people who signed the petitions didn”t know what it would do.

“The initiative process has no place for deceit and deception,” said Alan Gottlieb, founder of the Second Amendment Foundation. “A few billionaires donated millions of dollars to buy the signatures to get this fraudulent initiative on the ballot, but they couldn”t buy the court.”

Microsoft co-founder Paul Allen was among the backers of the measure.

I-1639 would raise the age for the purchase of a semi-automatic rifle to 21. It would also expand the background checks for the purchase of these rifles. The measure would require people to complete a firearm safety training course and create standards for safely storing firearms.

The Alliance for Gun Responsibility, the group behind the initiative, has filed a notice of appeal with the Washington Supreme Court.

Alliance CEO Renee Hopkins called the judge”s decision “shocking.”

“The right of Washingtonians to make changes to our laws via initiative has been part of our state”s history for more than 100 years and is fundamental to the Washington we know today,” Hopkins said. “Today”s decision tossed out the signatures of more than 378,000 voters, and undermined the rights of the citizens of this state in favor of the interests of the gun lobby. It”s not right, and we will continue to fight.”

Secretary of State Kim Wyman, who certified the petitions July 27, said the judge”s guidance will allow them to proceed with election preparations on schedule.

“No matter the issue, this office has a long track record of protecting the people”s constitutional right to initiative and referendum,” Wyman said in an email. “Whenever questions are raised about petitions submitted by initiative-backers facing a statutory deadline, my office has consistently acted accordingly.”

Wyman”s spokesman, Erich Ebel, said the case would likely be heard by the state Supreme Court next week.

The alliance describes the initiative as a comprehensive gun violence prevention measure that addresses a number of issues.

“Washingtonians already made it clear that they want stronger gun laws,” said Stephen Paolini, campaign manager for Initiative 1639: Safe Schools, Safe Communities. “That”s why hundreds of thousands of people signed Initiative 1639. Those voters deserve the opportunity to vote on a measure they support. It”s disappointing and unacceptable that the court would ignore the obvious and clear interests and desires of Washingtonians to keep their schools and communities safe.”

Gottlieb said the main problem with the petitions was that they didn”t contain underlines to show what would be added to the law, or “strike-through” lines to show the parts of the law that would be removed.

Chris Cox, executive director of NRA”s Institute for Legislative Action, said the group was glad that the judge recognized “how negligent, if not worse, gun control advocates were in their signature-gathering for this ill-advised ballot initiative.”